The 36-year-old has warned United’s Premier League rivals that Ferguson’s Old Trafford rule is set to go on for years to come.

Giggs has been the common denominator in every one of the United manager’s 11 title successes and insists he has seen nothing to suggest he is ready to wind down.

Ferguson celebrates 24 years in the job this November, winning 25 major honours.

At the age of 68 he is determined to win a third Champions League trophy before walking away from the sport, as well as leading United to a record 19th league title to move them past Liverpool.

But Giggs is adamant that even if Ferguson achieved both of those ambitions this season, it still wouldn’t be enough to convince him to retire.

“People probably thought 10 years ago that he would have packed it in by now,” said the Welsh winger. “He still enjoys the challenge. You can see him at training – he’s still enthusiastic.

“He’s got a good team and he enjoys working with the players. I think even if he won the lot this year, he’d still carry on.

“For him it’s not about that – it’s whether he enjoys it. And if that’s the case, he will go on.

“His future is not determined by what we win. When he feels he hasn’t got the drive or hunger to push the team on, that’s when he’ll know he’s had enough.”

Ferguson has continually refused to set a retirement date having gone back on his decision to quit in 2002.

That heralded a whole new period of success for United, which has seen them win three more titles and a second Champions League.

Chelsea challenge

Ferguson is once again building a new generation at the club as he bids to win the title back from Chelsea.

And Giggs admits a 12th Premier League is his main motivation heading into the new season.

The most decorated player in the history of English football says the chance to be champions once more would be his final dream if he hung up his boots at the end of the campaign.

“If I could win just one more trophy, what would it be?” he said. “Premier League or Champions League?

“I think I’d like to win another title. Then we’d have more than Liverpool.”

Given the incredible longevity of both Giggs and Ferguson, the question is, which one will pack it in first?

But should the manager be the first to call it a day, who would Giggs choose as his successor?

“It’s so hard because no-one knows when he’ll feel it’s time to retire,” he said.

“It could be two years, it could be 10 and in that time candidates will come and go because there are so many ups and downs in the job.

“There are two ways of looking at it. You could go for the young, up and coming, hungry manager or the more experienced like Jose Mourinho or Fabio Capello.

“You just don’t know, but whoever it is, it’s going to be a tough job to follow. When clubs usually get a new manager it is because they are struggling. They might also need to buy players so they will need time for everyone to settle. You wouldn’t expect that to be the case here. It will be a difficult job.”

A host of ex-United players have been tipped as long-term successors to Ferguson, only to see their stock fall.

Bryan Robson, Roy Keane and Mark Hughes were all seen as potential future United managers, but major European names like Mourinho, Pep Guardiola and Laurent Blanc are now regarded as more likely replacements.

“I don’t think it matters where the next manager is from,” said Giggs. “Whether he’s foreign or British.

“Ideally, as a United fan, you want it to be an ex-player, but that doesn’t have to be the case.

The Premier League is so cosmopolitan now with so many foreign players, you just want the best man for the job.”

And does Giggs see himself as future United boss?

“Two or three years ago I started my coaching badges,” he said. “I just want to be prepared for when I finish.

“There are some players who you think will definitely go into management when they finish – I’m not one of them at the moment.

“I want to be involved on some level, but whether it’s managing or coaching I don’t know.

“I’ve always said for me that the biggest job would be managing United or Wales. I captained my country and that was a dream. If I was a manager, it would be my dream to manage them as well.”

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